So far, 91 people have died from the lethal H5N1 bird flu strain.
Two dead swans in northern Germany and two birds found dead in Austria appear to have been infected with the virus, health officials in both countries reported.
The German swans were found on the island of Ruegen and regional agriculture ministry spokeswoman Iris Uellendahl said a preliminary test showed it was H5N1.
Agriculture Minister Horst Seehofer was scheduled to hold a news conference later Tuesday.
Samples from the birds were being take to an EU laboratory in Britain for a definitive test, Uellendahl said. Poultry within 2 miles of where the dead swans were found would be tested, she said.
Earlier Tuesday, Seehofer ordered that all domestic birds be kept indoors starting next week, moving up the previously planned measure to prevent migrating fowl from possibly spreading the virus.
Seehofer ordered farmers to enclose all poultry and other domestic birds in barns or cages with roofs starting Feb. 20. Authorities determined there was a heightened risk following the discovery of H5N1 in, the first time the highly infectious strain had been detected in the 25-member EU.
H5N1 also has occurred in birds in Asia,and the Middle East.
Germany initially had planned to order all birds indoors for at least two months starting March 1.
In Iran, the deadly strain of bird flu has killed 135 wild swans on the Caspian Sea coast, the first such cases detected in the Islamic Republic, the government said Tuesday.
Iran's official Islamic Republic News Agency said laboratory tests confirmed the H5N1 strain killed the swans at two locations in the Anzali marshlands during the past two weeks.
Iran's Veterinary Organization said all meat provided under Health Ministry regulations in Iran were free from bird flu and not dangerous to humans, IRNA said.
Meanwhile, Russia announced plans to begin human tests of a potential bird flu vaccine in April, the country's chief epidemiologist said Tuesday. Also Tuesday, Albania and Macedonia banned poultry imports from Greece, Italy, Bulgaria and Slovenia, where the H5N1 bird flu strain was detected over the weekend, authorities said.
Albania and Macedonia have not recorded any H5N1 cases. Albania was also buying protective clothing and stockpiling antiviral drugs in case the disease reached the tiny Balkan country.
Russian news agencies quoted Gennady Onishchenko as saying that the tests will be conducted on volunteers and "over a period of five weeks we will observe how the people's immune systems react."
The reports did not specify how the volunteers would be solicited or how the vaccine would be administered.
Russia first reported the H5N1 bird flu strain, which can kill humans, appearing in Siberia in July and it has since been recorded in other parts of the country. No human deaths from the virus have been reported in Russia.
But Onishchenko was quoted as warning that the virus could again begin spreading this spring as birds begin northern migration from their winter nesting grounds in Africa.
The migration routes do not cross the heavily populated areas around Moscow, "but a few (of the birds) could fly here," he said, according to the RIA-Novosti news agency.
In the Caspian Sea region of Dagestan, meanwhile, officials said massive poultry deaths at two farms have been attributed to Newcastle disease, denying reports that said crows with bird flu symptoms were found at one of the farms.
Newcastle disease is a contagious viral disorder that poses no danger to humans.
In neighboring Ukraine, President Viktor Yushchenko said Tuesday that his country and Russia would create a joint commission to fight bird flu. In December, the disease was recorded on the Ukraine's Black Sea Crimean Peninsula.
Imports from other Asian and European countries with bird flu cases have been banned in Albania, and authorities urged its citizens to avoid contact with dead birds. Hunting wild birds has been prohibited, and experts were regularly checking lagoons for sick or dead birds.
H5N1 has decimated poultry stocks in Asia and killed dozens of people in Asia and Turkey, with most human victims infected directly by sick birds. Scientists fear, however, that the strain could mutate into a form that can spread more easily between people and spark a pandemic.
Separately, Albania banned cattle imports last week from Argentina, Turkey and Brazil, following cases of foot-and-mouth disease in those countries.
Indonesia reported its latest bird flu death Tuesday, a 23-year-old man, while four members of a family were being treated in a hospital for symptoms of the virus.
The government said it will intensify the slaughtering of fowl in bird flu-infected areas.
The man died in Jakarta on Sunday, said senior health ministry official Hariadi Wibisono. Tests by a local laboratory showed he had bird flu, but samples were sent to a World Health Organization lab in Hong Kong for confirmation.
The family under observation lived in west Java province and had contact with chickens, said Sardikin Giriputro, an official at Jakarta's infectious diseases hospital. Tests were being conducted to see whether they had bird flu.
As of Monday, WHO had confirmed 25 human bird flu cases in Indonesia, 18 of which were fatal.
Almost all the human deaths have been linked to contact with infected poultry, but experts fear the H5N1 strain of the virus could mutate into a form that spreads easily among people, possibly starting a human flu pandemic.
The virus has killed at least 91 people in Asia and Turkey since 2003, according to the World Health Organization. Almost all the human deaths have been linked to contact with infected poultry, but experts fear H5N1 could mutate into a form that spreads easily among people, possibly starting a human flu pandemic.